Resin impregnating system

ABSTRACT

A resin impregnating system in the form of an open-ended tubular housing or canister is provided with a pair of flexible rubber seals at the transverse open ends to accommodate the reinforcing material forming part of a reinforced plastic member passing through the housing. The housing is provided with a suitable resin matrix material which is capable of impregnating the reinforced plastic member passing through the housing. The reinforced plastic member is typically formed of a textile strand material which is capable of receiving the resin matrix. Transducers capable of being operated by sonic energy are located in the housing for forcing the resin into the textile strand material. Another embodiment of the invention discloses a canister divided into two compartments where the first compartment is maintained under vacuum conditions for removing any entrained air in the textile strand material. The member passes immediately from the first compartment into the second compartment which is maintained under pressure for forcing the resin matrix into the voids left by the removed air in the textile strand material.

United States Patent 1 Hardesty [451 June 5, 1973 [54] RESINlMPREGNATlNG SYSTEM [75] Inventor: Ethridge E. Hardesty, Pine Valley,

Calif.

[73] Assignee: Goldsworthy Engineering, Inc.

[22] Filed: Feb. 16, 1971 [21] Appl. No.: 115,514

7/1969 Torigai et al. 12/1964 Orsini ..425/1 13 Primary Examinerl-l. A.Kilby, Jr. Attorney-Robert J. Schaap, Neal E. Willis and John D. Upham[57] ABSTRACT A resin impregnating system in the form of an openendedtubular housing or canister is provided with a pair of flexible rubberseals at the transverse open ends to accommodate the reinforcingmaterial forming part of a reinforced plastic member passing through thehousing. The housing is provided with a suitable resin matrix materialwhich is capable of impregnating the reinforced plastic member passingthrough the housing. The reinforced plastic member is typically formedof a textile strand material which is capable of receiving the resinmatrix. Transducers capable of being operated by sonic energy arelocated in the housing for forcing the resin into the textile strandmaterial. Another embodiment of the invention discloses a canisterdivided into two compartments where the first compartment is maintainedunder vacuum conditions for removing any entrained air in the textilestrand material. The member passes immediately from 11 Claims, 5 DrawingFigures VACUUM PATENIED 5'975 3,737, 261

SHEET 1 BF 2 INVENTOR F i G 3 ETHRIDGE E. HARDESTY Mm ha W ATTORNEYPATENIEUJUH 5|973 SHEET 2 UP 2 INVENTOR ETHRIDGE E. HARDESTY ATTORNEYRESIN IMPREGNATING SYSTEM This invention relates in general to certainnew and useful improvements in resin impregnating devices, and moreparticularly, to an improved resin impregnating device for effectivelyresin impregnating textile strand material.

In recent years, the use of fiber reinforced composites has receivedwidespread acceptance. With the advent of more effective and efficientmanufacturing systems, tanks, pipes, high pressure bottles, and similarstructures are now being fabricated from reinforced plastic compositematerials where they were formerly made from steel, other heavy metals,or other conventional materials of construction.

The increased technology in the manufacturing of articles fromreinforced plastic materials has enabled these articles to be made atrelatively high production rates. This increase in production hasresulted in a demand for more effective resin impregnating systems. Ithas been found that the filament strand material must be efficientlyimpregnated with a suitable curable resin matrix in order to render anefficient end product. However, while the machinery capable of producingthe end reinforced plastic product has been improved dramatically,relatively little attention has been directed to a suitable techniquefor resin impregnating the strand material which is used in the makingof the reinforced plastic composite. Typically, most of the extantmachinery relies upon a well-known conventional dip-tank, where thestrand material is merely brought into contact with a resin in a troughor tank.

This resin impregnating system has proved to be relatively ineffectivein that if the strand material is closely bunched together duringintroduction into the resin solution, some of the strand material is notsufficiently impregnated. Furthermore, in many cases the strand materialmay receive an excess amount of resin. Either of these situationsresults in an end product which is either resin-rich or resin-poor andthis condition substantially affects the overall desired strengthcharacteristics in the final product.

It is, therefore, the primary object of the present invention to providea resin impregnating system which is capable of being regulated toprovide a preselected quantity of resin matrix to a filamentary strandmaterial.

It is another object of the present invention to provide a resinimpregnating system of the type stated which is relatively economical tomanufacture and which is also highly efficient in its operation.

It is a further object of the present invention to provide a resinimpregnating system of the type stated which is capable of effectivelyremoving entrained air in the filamentary strand material and replacingthe entrained air by a suitable quantity of resin matrix.

With the above and other objects in view, my invention resides in thenovel features of form, construction, arrangement, and combination ofparts presently described and pointed out in the claims.

In the accompanying drawings:

FIG. 1 is a perspective view of a resin impregnator constructed inaccordance with and embodying the present invention;

FIG. 2 is a vertical sectional view taken along line 22 of FIG. 1;

FIG. 3 is a vertical sectional view of a modified form of resinimpregnator constructed in accordance with and embodying the presentinvention;

FIG. 4 is a vertical sectional view of another modified form of resinimpregnator constructed in accordance with and embodying the presentinvention; and

FIG. 5 is a schematic side elevational view partially broken away andshowing the use of the resin impregnator of the present invention inconjunction with a filament winding apparatus.

Generally speaking, the resin impregnator of the present invention isconstructed in the form of a tubular canister or housing which isopen-ended. The housing is provided with a central bore having aninterior angular side wall which is slightly spaced from the exteriorsurface of a tubular member passing through the open ends of thehousing,The housing may also be provided with a flexible tube to providea source of resin matrix. At each of the transverse ends of the housing,inflatable seals are provided. The seals are inflated to engage the tubepassing through the housing with the desired amount of pressure to bemaintained on the tube. These seals prevent any of the resin matrix fromoozing outwardly of the housing and to maintain proper pressure withinthe housing in order to provide the desired amount of impregnation.

Another form of resin impregnator of the present invention includes aseries of axially spaced circumferentially disposed plates which serveas force transducers and are sonically driven by means of a sonic energygenerator. This form of housing is also provided with the inflatableseal at each of the transverse ends.

As further modification of the present invention, an open-ended tubularhousing is provided with two compartments. The first of thesecompartments is maintained under a vacuum so that the tubular structurewhich is introduced into the housing is subjected to the vacuumconditions. The vacuum is effective to remove any entrained air in thefilamentary strand material which forms part of the tubular member. Thetubular structure is thereafter immediately passed into a sec- .ondcompartment where the compartment is maintained under pressure and thetubular member is brought into contact with the resin matrix. The resinmatrix which is maintained under pressure is thereuponforced into thevoids of the tubular member which remain after removal of the entrainedair. Force transducers may also be located in this latter compartment ofthe housing. Inflatable rubber seals are also located on each of thetransverse ends of the housing and are located intermediate between thetwo sections in order to maintain the proper pressure conditions.

Referring now in more detail and by reference characters to the drawingswhich illustrate practical embodiments of the present invention, Adesignates a resin impregnator which comprises an outer housing 1 havingright and left end walls 2, 3. The housing 1 is provided with axiallyextending aperture or central bore 4 capable of receiving an article Tsuch as a tubular member made of reinforced plastic material.

The open ended tubular housing or so-called canister" 1 is circular invertical cross section and includes a relatively thick annular wall 5which forms the central bore 4. The annular wall 5 is provided with aseries of axially spaced circumferentially disposed circular plates 6which serve as force transducers or so-called sonic drivers. Each of theplates 6 is in turn connected to a suitable sonic energy generator (notshown) for generating the necessary energy to drive the resin into thetubular member passing into the housing 1.

At each transverse end, the interior surface of the annular wall 5 isprovided witha neoprene rubberseal' T having an internal diameterwhichis sufficient to enable a filament wound tube T to pass therethrough. Byreference to FIG. 2, it can be seen that the seals 7 are sized toaccommodate the tube T as it passes through the housing 1. Furthermore,the seals 7 are sufficiently flexible to yield in order to accommodatenonlinearities in the circular dimension of the tube T passing throughthe housing 1. The seals 7 are also sufficiently rigid to maintain asubstantially fluid-tight engagement between the surface of the tube Tand the interior of the housing 1. While the distance existing betweenthe exterior surface of the tube T and the interior surface of theannular wall 7 has been illustrated as being rather large, thisillustration is only for purposes of describing the present invention.However, it should be recognized that this annulus has a substantiallysmall thickness and that the exterior surface of the tube T is only veryslightly spaced from the interior surface of the wall The housing 1 isalso provided with a fitting 8 and a tube 9 connected to a suitablesource of liquid resin (not shown). In this manner, it is possible tocontinually supply a resin matrix to the housing 1. In like manner, thehousing 1 is also provided with an upwardly extending hollow standpipe10 which serves as an air accumulator. The standpipe 10 is provided witha removable cap 11 and a sight glass 12 which extends for the greaterportion of the vertical length of the standpipe 10. Air which has beenentrained in the various strands of the filament will be displaced bythe liquid resin as the strands enter into the housing l.-This air willbe normally biased into the standpipe 10 where it will displace andforce downwardly the liquid resin therein. The amount of the displacedair which has accumulated in the standpipe 10 can be observed throughthe sight glass 12 from time to time. After a sufficient quantity of airhas been accumulated, the cap 11 can beremoved for bleeding off theaccumulated air. As this occurs, the standpipe will normally be filledwith the resin under pressure. It can be observed that the same pressureconditions will always be maintained within the housing 1 regardless ofthe amount of air which has been accumulated in the standpipe 10.

It has been found that the use of sonic energy is very effective inurging the resin material into the strands which form the tube T. Itshould be recognized that the tube T may be slightly resin wetted priorto its entry into the housing. This is often desirable and it has beenfound that the rate of impregnation increases rapidly when the surfaceof the tubular member has been resin wetted. The resin wetting can occurby any conventional technique. Furthermore, it should be observed thatthe filamentary strands which form the tubular member are oftentimesclosely bound together. Typically, the strands may have been applied toa mandrel in such fashion that the tube comprises longitudinal strands,helical strands, and circumferential strands. This type of closely knitstructure oftentimes prevents complete impregnation of the strandslocated at the innermost portion of the tube. However, it has been foundthat by forcing the resin matrix into the tubular structure T throughthe use of sonic energy, that essentially all strands are suitablecoated.

It should also be observed that the present invention is not limited tothe application of resin to tubular members, per se. It has been foundthat this type of resin' applicator, is suitable for impregnating manyforms of structures which have been formed of filamentary strandmaterials.

As used herein, the term sonic is not limited to that energy sourcewhich is within the normal hearing range, namely 16 cycles per second to16 kilocycles per second. The term sonic also includes the subsonicrange which is approximately 0 to 60 cycles per second, the ultrasonicrange which is approximately 17 kilocycles per second to 780 kilocyclesper second and the hypersonic range which is approximately 1 megacycleper second to approximately 15 megacycles per second, as well as thesonic range.

Any large number of resin matrix materials can be used in the resinimpregnator of the present invention. Typically, the resin selectedwould be dependent upon the end product which is to be produced and thetype of filamentary material which is employed in the reinforced plasticcomposite. Some examples of suitable resin matrix materials which can beemployed in the present invention are various thermoplastic resins suchas nylon, polyethylene, polypropylene, many of the polycarbonates,polyesters, etc. Other resin matrix materials which can be employed arewaxes, eutectic ceramics, eutectic metals, synthetic rubbers, etc.

It is also possible to provide a modified form of the present inventionwhich is more fully illustrated in FIG. 3 and which discloses a contactresin impregnator B. The resin impregnator B generally comprises anopenended tubular housing 13 which is circular in vertical cross sectionand has an annular side wall 14 with a central bore 15. The housing 14is provided with an interior annular side wall 16 which is slightlyspaced from the exterior surface of the tube passing through the bore 15thereby forms an annulus l7 therebetween. The housing 13 is alsoprovided with a fitting l8 and a flexible tube 19 connected'to somesuitable source of resin matrix (not shown). In like manner, the housing13 is also provided with an upstanding standpipe 20 having a removablecap 20 for accumulation of entrained air. The standpipe 20 is alsoprovided with a sight glass 21 for observing the amount of air which hasaccumulated therein.

At each of its transverse ends, the housing 13 is provided withinflatable seals 22, 23. The seals 22, 23 are conventional in theirconstruction and may be provided with a nipple or similar valvestructure for providing an air seal. The seals may be inflated to engagethe tube passing through the bore 15 with the desired amount of pressureOn the tube. The rear seals l2 are inflated generally witha low airpressure source in order to maintain the proper pressure in the housing23 to prevent any of the liquid resin from oozing outwardly through theseal 22. The forward seal 23 is regulated with pressure in order toobtain the proper resin deposition on the exterior surface of the tube.If the seal 23 was inflated with only a slight amount of pressure, thena fairly thick resin coating would exist on the surface of thevtube. Inlike manner, if the seal 23 was inflated to afairly high pressure, itwould engage the side wall of the tube passing through the housing 23with a fair amount of pressure and prevent a resin rich coating fromexisting on the surface of the tube as it passed through the housing 23.Furthermore, by inflating the seal 23 to a fairly substantial pressure,the seal will serve as a type of wiper and in essence serve to removesome of the resin matrix which may exist on the exterior surface of thetube T.

It is also possible to provide another modified form of resinimpregnator C which is more fully illustrated in the sectional view ofFIG. 4. The resin impregnator C generally comprises an open-endedtubular housing or canister 30 which is circular in vertical crosssection and includes a relatively thick annular wall 31 which forms acentral bore 32. At each transverse end, the interior surface of theannular wall 31 is provided with a neoprene rubber seal 33 having aninternal diameter which is sufficient to enable the filament wound tubeT to pass therethrough. An intermediate seal 34 is located midwaybetween each of the transverse end seals 33 thereby dividing the housing30 into a vacuum compartment 35 and a pressure compartment 36. Byfurther reference to FIG. 4, it can be seen that the seals 33, 34 aresized to accommodate the tube T as it passes through the housing 30.Furthermore, the seals 33, 34 are sufficiently flexible to yield inorder to accommodate nonlinearities in the circular dimension of thetube T passing through the housing 30. In like manner, the seals 33, 34are often sufficiently rigid to maintain a substantially fluid-tightengagement between the surface of the tube T and the interior of thehousing 30 as well as between the two compartments 35, 36.

The housing 30 is also provided with a fitting 37 in the area of thevacuum compartment 35 which is, in turn, connected to a suitable pump orthe like (not shown) in order to impose a vacuum on the vacuumcompartment 35. It can be seen that the fitting 37 extends through thethick annular wall 31 and opens into the central bore 32 in order tocreate a vacuum condition therein. Thus, as the tube T is passingthrough the housing, the right-hand end seal 33 and the intermediateseal 34 maintain contact with the exterior surface of the tube T to holdthe vacuum condition in the compartment 35. Furthermore, the seal 34 issufficient to prevent any of the pressure in the compartment 36 fromextending into the vacuum compartment 35.

The annular wall 31 in the area of the pressure compartment 36 isprovided with a series of axially spaced circumferentially disposedcircular plates 38 which serve as force transducers or sonic drivers.Each of the plates 38 is in turn connected to a suitable sonic energygenerator (also not shown) for generating the necessary energy to drivethe resin into the tubular member passing through the housing 30. Thehousing is also provided with a fitting 39 and a tube 40 connected to asuitable source of liquid resin (not shown). In this manner, it ispossible to continually supply a resin matrix to the housing 30.

The housing 30 is also provided with an upwardly extending hollowstand-pipe 41 which serves as an air accumulator. The standpipe 41 isprovided with a removable cap 42 and a sight glass 43 which extends forthe greater portion of the vertical length of the stand pipe 41. Any airwhich has been entrained in the various strands of the filament andwhich may not have been removed in the vacuum compartment 35 can bedisplaced by the liquid resin as the strands enter into the compartment36. This air will be normally biased into the stand pipe 41 where itwill displace and force downwardly the liquid resin therein. It shouldbe observed that resin can also be introduced into the compartment 36under pressure thereby obviating the employment of the sonic energydrivers. In either event, the resin which is introduced into thecompartment 36 will normally flow into the interior portions of thestrands since the resin in maintained under pressure and since voids nowexist where air has been removed in the compartment 35.

FIG. 5 schematically discloses a filament winding apparatus for makingfilament reinforced tubular structures and which employs any of theresin impregnators A-C. The filament winding apparatus F generallycomprises a base plate 50 and mounted on one end thereof is a spool rack51 having a series of conventional spools of filament or so-calledroving thereon. The roving is trained through a series of eyelets 53 andapplied to a fixed mandrel 54 so that the strands are axially disposedwith respect to the mandrel 54, to form a series of longitudinalstrands. The strands are passed through a resin applicator R, which isequivalent to any of the resin applicators A-C. Thereafter, a series ofwinding stations, W W are located to the left of the resin applicator Rfor applying either helical or circumferential wound strands to thelongitudinal strands. Thereafter, another applicator R, which isequivalent to any of the applicators A-C is also provided.

It should be recognized that this filament winding system is only one ofthe many possible uses in which the resin applicators A-C can beemployed.

It should be understood that changes and modifications in the form,construction, arrangement and combination of parts presently describedand pointed out may be made and substituted for those herein shownwithout departing from the nature and principle of my invention.

Having thus described my invention, what I desire to claim and secure byLetters Patent is:

1. A device for impregnating a resin matrix curable material into theindividual closely wound impregnatable textile fiber strands of a hollowtubular member when said tubular member is retained on and moving alonga fixed rigid mandrel and where each strand is formed of a plurality oftextile filaments, said device comprising a tubular housing having openentrant and exit end portions and a central bore formed by an interiorwall extending between said open end portions, means operativelyassociated with said housing for introducing said matrix curablematerial into said central bore, means also operatively associated withsaid housing to force said resin matrix into said plurality of closelywound strands and into intimate contact with each of the filaments influid of said strands as said strands move along said mandrel, a fluidexpandable sealing ring operatively located at each of said open endportions for engaging said strands and forming a sliding liquid sealbetween said strands and said sealing rings as said strands move throughsaid housing, fluid supply means operatively associated with each ofsaid sealing rings to permit a fluid to be introduced into said rings topermit expansion and contraction responsive to the amount of fluidintroduced thereinto, to thereby maintain preselected pressureengagement with the hollow tubular member and to adjust surfacenonlinearities in said hollow tubular member, individual fluid supplytubes operatively connected to said fluid supply means and respectiveones of said sealing rings for independently controlling the fluidintroduced into the sealing ring at said entrant end portion to controlpressure condtions in said central chamber and the amount of oozing ofthe matrix curable material out-' wardly of said ring and forindependently controlling the amount of fluid to be introduced into thesealing ring at said exit end portion to thereby control the amount ofmatrix material impregnation in said strands and the amount of resinmaterial remaining on the surface of said strands, said mandrelextending through said housing and beyond the sealing ring at the exitend portion thereof so from the the impregnated strands may beultimately cured and removed from the mandrel as the final structuraltubular member.

2. The device of claim 1 further characterized in that energizable meansis operatively associated with said housing capable of producing sonicenergy for forcibly urging said matrix curable material into initmatecontact with said strands.

3. The device of claim'l further characterized in that at least onetransducer plate is located in said housing and surrounding said centralbore and being operatively connectable to a mechanism capable ofproducing a source of sonic energy for applying said sonic energy acrosssaid central bore to forcibly urge said matrix curable material intointimate contact with said strands.

4. The device of claim 1 further characterized in that said housing ismaintained under pressure in the area of said central bore to therebyforcibly urge said matrix curable material into intimate contact withsaid strands.

5. A device for impregnating a resin matrix curable material into theindividual closely wound impregnatable textile fiber strands of a hollowtubular member when said tubular member is retained on and moving alonga fixed rigid mandrel and where each strand is formed of a plurality oftextile filaments, said device comprising a tubular housing having anelongated outer wall, an intermediate wall in said housing forming afirst chamber and entrant axially aligned second chamber, said housinghaving an extrant open end portion communicating with said first chamberand an exit open end portion communicating with said second chamber,means forming an aperture in said intermediate wall permittingcommunication between said two chambers, means operatively associatedwith said first chamber for creating a vacuum therein to removeentrained air from said strands as said strands move along said mandrel,means operatively associated with said housing for introducing saidmatrix curable material into said second chamber, contact means alsooperatively associated with said housing to force said resin matrix intosaid plurality of closely wound strands and into intimate contact witheach of the filaments in each of said strands as said strands move alongsaid mandrel, a fluid expandable sealing ring operatively located ateach of said open end portions and in the aperture in said intermediatewall for engaging said strands and forming a sliding liquid seal betweensaid strands and said sealing ring as said strands move through saidhousing, fluid supply means operatively associated with each of saidsealing rings to permit a fluid to be intro duced into said rings topermit expansion and contrac-. tion responsive to the amount of fluidintroduced thereinto, to thereby maintain preselected pressureengagement with the hollow tubular member and to adjust surfacenon-linearities in said hollow tubular member, a first individual fluidsupply tube operatively connected to said fluid supply means and thesealing ring at entrant end portion for controlling the fluid introducedinto the sealing ring at said entrant end portion to control vacuumconditions in said first chamber, a'sec'ond individual fluid supply tubeoperatively connected to said fluid supply means and said sealing ringin said aperture for also independently controlling the amount of fluidto the sealing ring in said aperture to control vacuum conditions insaid first chamber and the amount of oozing of the matrix curablematerial from said second chamber, and a third individual fluid supplytube operatively connected to said fluid supply means and to the sealingring at said exit end portion for also independently controlling theamount of fluid to be introduced into the sealing ring at said exit endportion to thereby control the amount of matrix material impregnation insaid strands and the amount of resin material remaining on the surfaceof said strands, said mandrel extending through said housing and beyondthe sealing ring at the exit end portion thereof so that the impregnatedstrands may be ultimately cured and removed from the mandrel as thefinal structural tubular member.

6. The device of claim 5 further characterized in that the matrixcontact means enables said second chamber to be maintained underpressure for forcibly urging said matrix curable material into intimatecontact with said strands.

7. The device of claim 5 further characterized in that said matrixcontact means comprises energizable means capable of producing sonicenergy and which is operatively associated with said second chamber forforcibly urging said matrix curable material into intimate contact withsaid strands.

8. The device of claim 5 further characterized in that said matrixcontact means enables said second chamber to be maintained underpressure to thereby forcibly urge said matrix curablematerial intointimate contact with said strands, and means is operatively associatedwith said second chamber to automatically adjust for entrained air insaid strands to thereby maintain relatively constant pressure in saidsecond chamber.

9. The device of claim 1 further characterized in that said contactmeans comprises energizable means operatively associated with saidhousing for producing high frequency energy introduced with respect tothe resin matrix curable material contained within said chamber, saidmatrix curable material having energy coupling properties to couple theenergy with respect to said strands and thereby vibrate said strands tocause intimate contact of the matrix material with said strands andimpregnation thereinto.

10. The device of claim 9 further characterized in that the energizablemeans is capable of producing sonic energy for forcibly urging saidmatrix curable material into intimate contact with said strands.

11. The device of claim 10 further characterized in that saidenergizable means comprises. at least one transducer plate located insaid housing and surrounding said central bore and being operativelyconnectable to a mechanism capable of producing a source of sonic energyfor applying said sonic energy to said strands across said matrixcurable material to forcibly urge said matrixcurable material intointimate contact with said strands.

l k 0 I

1. A device for impregnating a resin matrix curable material into theindividual closely wound impregnatable textile fiber strands of a hollowtubular member when said tubular member is retained on and moving alonga fixed rigid mandrel and where each strand is formed of a plurality oftextile filaments, said device comprising a tubular housing having openentrant and exit end portions and a central bore formed by an interiorwall extending between said open end portions, means operativelyassociated with said housing for introducing said matrix curablematerial into said central bore, means also operatively associated withsaid housing to force said resin matrix into said plurality of closelywound strands and into intimate contact with each of the filaments influid of said strands as said strands move along said mandrel, a fluidexpandable sealing ring operatively located at each of said open endportions for engaging said strands and forming a sliding liquid sealbetween said strands and said sealing rings as said strands move throughsaid housing, fluid supply means operatively associated with each ofsaid sealing rings to permit a fluid to be introduced into said rings topermit expansion and contraction responsive to the amount of fluidintroduced thereinto, to thereby maintain preselected pressureengagement with the hollow tubular member and to adjust surfacenon-linearities in said hollow tubular member, individual fluid supplytubes operatively connected to said fluid supply means and respectiveones of said sealing rings for independently controlling the fluidintroduced into the sealing ring at said entrant end portion to controlpressure condtions in said central chamber and the amount of oozing ofthe matrix curable material outwardly of said ring and for independentlycontrolling the amount of fluid to be introduced into the sealing ringat said exit end portion to thereby control the amount of matrixmaterial impregnation in said strands and the amount of resin materialremaining on the surface of said strands, said mandrel extending throughsaid housing and beyond the sealing ring at the exit end portion thereofso from the the impregnated strands may be ultimately cured and removedfrom the mandrel as the final structural tubular member.
 2. The deviceof claim 1 further characterized in that energizable means isoperatively associated with said housing capable of producing sonicenergy for forcibly urging said matrix curable material into initmatecontact with said strands.
 3. The device of claim 1 furthercharacterized in that at least one transducer plate is located in saidhousing and surrounding said central bore and being operativelyconnectable to a mechanism capable of producing a source of sonic energyfor applying said sonic energy across said central bore to forcibly urgesaid matrix curable mAterial into intimate contact with said strands. 4.The device of claim 1 further characterized in that said housing ismaintained under pressure in the area of said central bore to therebyforcibly urge said matrix curable material into intimate contact withsaid strands.
 5. A device for impregnating a resin matrix curablematerial into the individual closely wound impregnatable textile fiberstrands of a hollow tubular member when said tubular member is retainedon and moving along a fixed rigid mandrel and where each strand isformed of a plurality of textile filaments, said device comprising atubular housing having an elongated outer wall, an intermediate wall insaid housing forming a first chamber and entrant axially aligned secondchamber, said housing having an extrant open end portion communicatingwith said first chamber and an exit open end portion communicating withsaid second chamber, means forming an aperture in said intermediate wallpermitting communication between said two chambers, means operativelyassociated with said first chamber for creating a vacuum therein toremove entrained air from said strands as said strands move along saidmandrel, means operatively associated with said housing for introducingsaid matrix curable material into said second chamber, contact meansalso operatively associated with said housing to force said resin matrixinto said plurality of closely wound strands and into intimate contactwith each of the filaments in each of said strands as said strands movealong said mandrel, a fluid expandable sealing ring operatively locatedat each of said open end portions and in the aperture in saidintermediate wall for engaging said strands and forming a sliding liquidseal between said strands and said sealing ring as said strands movethrough said housing, fluid supply means operatively associated witheach of said sealing rings to permit a fluid to be introduced into saidrings to permit expansion and contraction responsive to the amount offluid introduced thereinto, to thereby maintain preselected pressureengagement with the hollow tubular member and to adjust surfacenon-linearities in said hollow tubular member, a first individual fluidsupply tube operatively connected to said fluid supply means and thesealing ring at entrant end portion for controlling the fluid introducedinto the sealing ring at said entrant end portion to control vacuumconditions in said first chamber, a second individual fluid supply tubeoperatively connected to said fluid supply means and said sealing ringin said aperture for also independently controlling the amount of fluidto the sealing ring in said aperture to control vacuum conditions insaid first chamber and the amount of oozing of the matrix curablematerial from said second chamber, and a third individual fluid supplytube operatively connected to said fluid supply means and to the sealingring at said exit end portion for also independently controlling theamount of fluid to be introduced into the sealing ring at said exit endportion to thereby control the amount of matrix material impregnation insaid strands and the amount of resin material remaining on the surfaceof said strands, said mandrel extending through said housing and beyondthe sealing ring at the exit end portion thereof so that the impregnatedstrands may be ultimately cured and removed from the mandrel as thefinal structural tubular member.
 6. The device of claim 5 furthercharacterized in that the matrix contact means enables said secondchamber to be maintained under pressure for forcibly urging said matrixcurable material into intimate contact with said strands.
 7. The deviceof claim 5 further characterized in that said matrix contact meanscomprises energizable means capable of producing sonic energy and whichis operatively associated with said second chamber for forcibly urgingsaid matrix curable material into intimate contact with said strands. 8.The device of claim 5 further characterized in thaT said matrix contactmeans enables said second chamber to be maintained under pressure tothereby forcibly urge said matrix curable material into intimate contactwith said strands, and means is operatively associated with said secondchamber to automatically adjust for entrained air in said strands tothereby maintain relatively constant pressure in said second chamber. 9.The device of claim 1 further characterized in that said contact meanscomprises energizable means operatively associated with said housing forproducing high frequency energy introduced with respect to the resinmatrix curable material contained within said chamber, said matrixcurable material having energy coupling properties to couple the energywith respect to said strands and thereby vibrate said strands to causeintimate contact of the matrix material with said strands andimpregnation thereinto.
 10. The device of claim 9 further characterizedin that the energizable means is capable of producing sonic energy forforcibly urging said matrix curable material into intimate contact withsaid strands.
 11. The device of claim 10 further characterized in thatsaid energizable means comprises at least one transducer plate locatedin said housing and surrounding said central bore and being operativelyconnectable to a mechanism capable of producing a source of sonic energyfor applying said sonic energy to said strands across said matrixcurable material to forcibly urge said matrix curable material intointimate contact with said strands.